The Seabird Program of the USA-based NGO American Bird Conservancy (ABC) has reported to the ACAP Secretariat on its recent efforts to reduce seabird mortality in Ecuador’s artisanal longline fishery.  The following information is taken from the ABC press release.

A new technique designed to reduce bycatch in Ecuadorian fisheries of seabirds such as the Critically Endangered Waved Albatross Phoebastria irrorata and the Vulnerable Black Petrel Procellaria parkinsoni was presented at a recent meeting with representatives of Ecuador’s Environmental Ministry.

The Waved Albatross is often attracted by baited hooks and can become entangled in line and hooks, photograph by Giovanny Suarez/ABC

The meeting, which focused specifically on the issue of seabird bycatch in the artisanal hake fishery in Ecuador, was held in the offices of the Ministry of the Environment on 5 December 2014.  The new fishing innovation – known as the NISURI device – aims to reduce by up to 90% the time that baited fishing lines are cast in the water with bait visible to birds.  Line setting using this technique is cut from 8 to >20 minutes to 1-2 minutes.

Artisanal fishing boats, Santa Rosa, Ecuador, photograph by Nigel Brothers

Ecuadorian artisanal fishers use the  NISURI tube to reduce seabird interactions, photograph by Nigel Brothers

To employ the NISURI device, Ecuadorian fishers typically prepare up to 400 baited hooks and insert them into a 1.8-m long PVC plastic tube which holds the lines while protecting the bait from birds. The NISURI tube acts like a chute to deploy the lines without the possibility of hooks being caught in a fisher’s hand or a bird’s bill while the boat is underway.

At the conclusion of the meeting the participants agreed to continue to work together to promote the new method and expand its use in artisanal hake fisheries through supporting fishers’ workshops in other ports in Ecuador.

A paper on the NISURI system was presented and discussed at the Sixth Meeting of the ACAP Seabird Bycatch Working Group, held in Punta del Este, Uruguay during September this year.

With thanks to Hannah Nevins, American Bird Conservancy for information.

Selected literature:

Brothers, N., Holly Freifeld, H., Suarez, G. & Wallace, G. 2014.  NISURI Fastset – a simple, cheap and effective artisanal demersal longline setting system to reduce seabird bycatch.  Sixth Meeting of the Seabird Bycatch Working Group Punta del Este, Uruguay, 10 - 12 September 2014.  SBWG6 Doc 14  [Summary]  3 pp.

John Cooper, ACAP Information Officer, 02 January 2015, updated 09 and 13 January 2015

Pedro Alvito (MARE-Marine and Environmental Research Centre, University of Coimbra, Portugal) and colleagues have written in the journal Polar Biology on the squid diet of non-breeding Black-browed Thalassarche melanophris and Grey-headed T. chrysostoma Albatrosses

The paper’s abstract follows:

“The food and feeding ecology of albatrosses during the nonbreeding season is still poorly known, particularly with regard to the cephalopod component.  This was studied in black-browed Thalassarche melanophris and grey-headed T. chrysostoma albatrosses by analysing boluses collected shortly after adults returned to colonies at Bird Island, South Georgia (54°S, 38°W), in 2009.  Based on stable isotopic analyses of the lower beaks, we determined the habitat and trophic level (from δ¹³C and δ¹⁵N, respectively) of the most important cephalopods and assessed the relative importance of scavenging in terms of the albatrosses’ feeding regimes.  Based on lower rostral lengths (LRLs), the main cephalopod species in the diets of both albatrosses was Kondakovia longimana, by frequency of occurrence (F > 90 %), number (N > 40 %) and mass (M > 80 %). The large estimated mass of many squid, including K. longimana, suggests that a high proportion (>80 % by mass) was scavenged, and that scavenging is much more important during the nonbreeding season than would be expected from breeding-season diets.  The diversity of cephalopods consumed by nonbreeding birds in our study was similar to that recorded during previous breeding seasons, but included two new species [Moroteuthis sp. B (Imber) and ?Mastigoteuthis A (Clarke)]. Based on similarities in LRL, δ¹³C and δ¹⁵N, the squid consumed may have been from the same oceanic populations or region, with the exception of Taonius sp. B (Voss) and  , which, based on significant differences in δ¹⁵N values, suggest that they may have originated from different stocks, indicating differences in the albatrosses’ feeding regimes.”

Grey-headed Albatross, photograph by Richard Phillips

With thanks to Richard Phillips for information.

Reference:

Alvito, P.M., Rosa, R., Phillips, R.A., Cherel, Y., Ceia, F., Guerreiro, M., Seco, J., Baeta, A., Vieira, R.P. & Xavier,  J.C. 2014.  Cephalopods in the diet of nonbreeding black-browed and grey-headed albatrosses from South Georgia.  Polar Biology DOI 10.1007/s00300-014-1626-3.

John Cooper, ACAP Information Officer, 01 January 2015

Rachel Buxton and colleagues have had a paper accepted for publication in the journal Emu - Austral Ecology that uses playback of calls to assess levels of attraction of burrowing procellariids to potential new breeding sites.

The paper’s abstract follows:

“Attempts to establish seabird colonies at restoration sites using artificial visual and auditory social cues have had varying success rates, differing between sites and species.  The biological mechanisms responsible for this variation are poorly understood.  We used experimental call playback to test the attraction of three sympatric procellariid species to auditory social cues in northern New Zealand.  To test whether the size of nearby breeding colonies affected the level of response to call playback, audio recordings were broadcast from three similar locations with varying densities of breeding conspecifics within 1 km.  Grey-faced Petrel (Pterodroma macroptera gouldi) were attracted to conspecific vocalisation playbacks at all three sites and also to playbacks of other species.  Fluttering Shearwater (Puffinus gavia) were only attracted to playback at two locations.  Flesh-footed Shearwater (Puffinus carneipes) were not attracted to playbacks, broadcast from only one location.  For Grey-faced Petrels and Fluttering Shearwaters, response to call playback increased with increasing densities of nearby breeding conspecifics, suggesting there may be a relationship between attraction and the size of nearby potential source populations.  For some procellariid species call playback represents a cost-effective alternative to other active restoration approaches, such as translocation.  However, we caution that its effectiveness for individual species at different sites should be assessed at the outset of restoration initiatives.”

Flesh-footed Shearwater, photograph by Barry Baker

Reference:

Buxton, R., Jones, C., Moller, H. & Lyver, P. in press.  One method does not suit all: variable settlement responses of three procellariid species to vocalization playbacks.  Emu.

John Cooper, ACAP Information Officer, 31 December 2014

Diego Rubolini (Dipartimento di Bioscienze, Università degli Studi di Milano, Italy) and colleagues have published in the journal Ethology on colony attendance and foraging activity in Scopoli's Shearwaters Calonectris diomedea in relation to moonlight.

The paper’s abstract follows:

“Moonlight is known to affect the nocturnal behaviour and activity rhythms of many organisms.  For instance, predators active at night may take advantage from increased visibility afforded by the moon, while prey might regulate their activity patterns to become less detectable.  Many species of pelagic seabirds attend their colony only at night, in complete darkness, avoiding approaching their nest sites under moonlight.  This behaviour has been most often interpreted as an antipredator adaptation (‘predation avoidance’ hypothesis).  However, it may also reflect a lower foraging efficiency during moonlit nights (‘foraging efficiency’ hypothesis).  Indeed, moonlight may reduce prey availability because preferred seabird prey is known to occur at higher depths in moonlit nights.  Using high-accuracy behavioural information from data loggers, we investigated the effect of moonlight on colony attendance and at-sea nocturnal foraging in breeding Scopoli's shearwaters Calonectris diomedea.  We found that birds departing for self-feeding trips around the full moon performed longer trips than those departing around the new moon.  On nights when the moon was present only partly, nest burrow entrances took place largely in the moonless portion of the night.  Moreover, contrary to predictions from the ‘foraging efficiency’ hypothesis, nocturnal foraging activity increased according to moonlight intensity, suggesting that birds increased their foraging activity when prey became more detectable.  This study strengthens the idea that colony attendance behaviour is strictly controlled by moonlight in shearwaters, which is possibly related to the perception of a predation risk.”

Scopoli's Shearwater fledgling, photograph from BirdLife Malta

Reference:

Rubolini, D., Maggini, I., Ambrosini, R., Imperio, S., Paiva, V.H., Gaibani, G., Saino, N. & Cecere, J.G. 2014.  The effect of moonlight on Scopoli's Shearwater Calonectris diomedea colony attendance patterns and nocturnal foraging: a test of the foraging efficiency hypothesis.  Ethology DOI: 10.1111/eth.12338.

John Cooper, ACAP Information Officer, 30 December 2014